import { describe, test, expect } from 'bun:test'

import {
  withTimeout,
  getGlobalOscTimeout,
  getQueryOscTimeout,
} from '../terminal-color-detection'

/**
 * These tests document the timeout scenarios that could cause users to get stuck.
 * They verify that the timeout mechanisms work correctly.
 */

describe('OSC Timeout Protection Scenarios', () => {
  describe('Scenario 1: Terminal ignores OSC queries entirely', () => {
    test('withTimeout returns fallback value when promise never resolves', async () => {
      // Simulate a terminal that ignores the OSC query completely
      const neverResolvingPromise = new Promise<string>(() => {
        // This promise never resolves, simulating a non-responsive terminal
      })

      const startTime = Date.now()
      const result = await withTimeout(neverResolvingPromise, 100, 'fallback')
      const elapsed = Date.now() - startTime

      expect(result).toBe('fallback')
      expect(elapsed).toBeGreaterThanOrEqual(100)
      expect(elapsed).toBeLessThan(200) // Should not hang
    })

    test('returns null theme when detection hangs', async () => {
      const hangingDetection = new Promise<'dark' | 'light' | null>(() => {})

      const result = await withTimeout(hangingDetection, 50, null)
      expect(result).toBeNull()
    })
  })

  describe('Scenario 2: Terminal responds very slowly', () => {
    test('withTimeout returns fallback for slow responses', async () => {
      const slowPromise = new Promise<string>((resolve) => {
        setTimeout(() => resolve('slow-response'), 500)
      })

      const result = await withTimeout(slowPromise, 100, 'timeout-fallback')
      expect(result).toBe('timeout-fallback')
    })

    test('withTimeout returns actual value for responses within timeout', async () => {
      const fastPromise = new Promise<string>((resolve) => {
        setTimeout(() => resolve('fast-response'), 10)
      })

      const result = await withTimeout(fastPromise, 100, 'timeout-fallback')
      expect(result).toBe('fast-response')
    })
  })

  describe('Scenario 3: Timeout hierarchy', () => {
    test('global timeout is greater than query timeout', () => {
      const queryTimeout = getQueryOscTimeout()
      const globalTimeout = getGlobalOscTimeout()

      // Global timeout should be greater than individual query timeout
      // to allow for retries and cleanup
      expect(globalTimeout).toBeGreaterThan(queryTimeout)
    })
  })

  describe('Scenario 4: Race conditions in cleanup', () => {
    test('multiple timeouts racing dont cause issues', async () => {
      // Create multiple promises that might complete at similar times
      const promises = Array.from({ length: 10 }, (_, i) =>
        withTimeout(
          new Promise<number>((resolve) =>
            setTimeout(() => resolve(i), Math.random() * 100),
          ),
          50,
          -1,
        ),
      )

      const results = await Promise.all(promises)

      // All results should be either the resolved value or the timeout value
      for (const result of results) {
        expect(typeof result).toBe('number')
      }
    })

    test('cleanup happens even on timeout', async () => {
      // This test verifies that withTimeout properly cleans up its own timeout
      // even when the underlying promise doesn't resolve
      const neverResolves = new Promise<string>(() => {
        // This promise intentionally never resolves
      })

      // This should timeout and return the fallback value
      const result = await withTimeout(neverResolves, 50, 'timeout')
      expect(result).toBe('timeout')

      // Note: withTimeout cleans up its own setTimeout via the finally block
      // The underlying promise's resources would need to be cleaned up separately
    })
  })

  describe('Scenario 5: Subprocess detection safety', () => {
    test('global timeout is reasonable for user experience', () => {
      const globalTimeout = getGlobalOscTimeout()

      // Users shouldnt wait more than 3 seconds for theme detection
      expect(globalTimeout).toBeLessThanOrEqual(3000)

      // But it should be long enough to actually work
      expect(globalTimeout).toBeGreaterThanOrEqual(1000)
    })

    test('query timeout allows for network latency in SSH scenarios', () => {
      const queryTimeout = getQueryOscTimeout()

      // SSH terminals might have up to 200-300ms latency
      // Query timeout should accommodate this plus some buffer
      expect(queryTimeout).toBeGreaterThanOrEqual(300)
    })
  })

  describe('Scenario 6: Error handling', () => {
    test('rejected promises propagate through withTimeout', async () => {
      const rejectingPromise = Promise.reject(new Error('test error'))

      await expect(
        withTimeout(rejectingPromise, 100, 'fallback'),
      ).rejects.toThrow('test error')
    })

    test('timeout value can be any type', async () => {
      const hangingPromise = new Promise<{ theme: string }>(() => {})

      const objectResult = await withTimeout(hangingPromise, 50, {
        theme: 'default',
      })
      expect(objectResult).toEqual({ theme: 'default' })

      const hangingPromise2 = new Promise<number[]>(() => {})
      const arrayResult = await withTimeout(hangingPromise2, 50, [1, 2, 3])
      expect(arrayResult).toEqual([1, 2, 3])
    })
  })

  describe('Scenario 7: Stacked timeouts (defense in depth)', () => {
    test('inner timeout fires before outer timeout', async () => {
      const innerPromise = new Promise<string>(() => {})
      const innerResult = withTimeout(innerPromise, 30, 'inner-timeout')

      const outerPromise = withTimeout(innerResult, 100, 'outer-timeout')

      const result = await outerPromise
      // Inner timeout should fire first
      expect(result).toBe('inner-timeout')
    })

    test('outer timeout catches if inner timeout fails', async () => {
      // Simulate a case where inner timeout mechanism fails
      const brokenInnerPromise = new Promise<string>(() => {
        // This never resolves, simulating broken inner timeout
      })

      const result = await withTimeout(brokenInnerPromise, 50, 'outer-saved-us')
      expect(result).toBe('outer-saved-us')
    })
  })
})


